Rewrite ${((7^{11})(8^{11}))^{-5}}$ in the form ${7^n \times 8^m}$.
Solution: ${ ((7^{11})(8^{11}))^{-5} = (7^{(11)(-5)})(8^{(11)(-5)})} $ ${\hphantom{ ((7^{11})(8^{11}))^{-5}} = 7^{-55} \times 8^{-55}} $